Steel alloy



peratures ranging from 400 Patented Nov. 1, 1932 UNITED STATES PATENT OFFICE WILLIAM H. WOODHALL, OF ATTICA, INDIANA, ASSIGNOR TO THE HARRISON STEEL CASTINGS COMPANY, A CORPORATION OI INDIANA STEEL ALLOY No Drawing.

This invention relates to steel alloy and the method of producing same.

The main object of the invention is to produce an alloy steel which will give good 5 ductility and machinability together with a high elastic limit and ultimate strength; which will be especially adapted to resist wear and which may be produced cheaply enough to be used in a large variety of machinery, particularly in castings such as sprockets, idlers, and track shoes used in road building machinery, and other castings subject to excessive wear.

The alloy is particularly adapted for eastings which must be heat treated to bring out their particular properties, but it is also superior in strength and wearing qualities to regular carbon steel in its normalized and drawn condition.

lVhile the alloy of my invention may be produced at a comparatively low cost, it may be used efiiciently in place of steels which costsubstantially more to produce.

Preferably, the alloy contains the elements named, in proportions within the ranges stated: Per cent Molybdenum .05 to .50 Carbon .20 to .60

Manganese 1.00 to 1.50 Copper .90 to 1.50 Zirconium .05 to .30

A typical alloy embodying my invention is 5 as follows:

This alloy may be normalized at 1700 F., then heated to 1600 F., quenched in oil, and then drawn to any desired hardness, and

the resultant steel has high ultimate strength and high elastic limit, with varying degrees of ductility, as may be desired. Preferably the alloy is drawn from the uench at tem- The alloy steels of the present invention Application filed December 4, 1930. Serial No. 500,141.

can be readily hardened by heating above their critical ranges and then cooling in water, oil or air as may be desired for the particular properties wanted. After hardening, the alloy must be drawn by reheating.

The addition of zirconium in combination with the other alloy materials herein described, produces a much finer grain in the structure of the finished alloy, and consequently superior strength and durability in the finished products.

I claim:

1. A casting composed of a steel alloy containing carbon .20 to 00%, molybdenum .05 to manganese 1.00 to 1.50%, copper .30 to 1.50% and zirconium .15 to 30% and the balance substantially iron.

2. A casting composed of a steel alloy containing elements in substantially the proportions stated: carbon .43%, molybdenum 25%, copper 1.10%, manganese 1.25%. and zirconium .15 and the balance substantially iron.

3. A casting composition of a steel alloy containing carbon .20 to 50%; molybdenum .05 to 50%; manganese 1.00 to 1.50%; coper .90 to 1.50%; and zirconium over .15 to 30% and the balance substantially iron.

In testimony, that I claim the foregoing as my invention, I aflix my signature, this 29th day of November, 1930.

WILLIAM-H. WOODHALL. 

